We know that these objects are out there, but what are scientists doing to locate them? And how would we respond if one were found to be on a collision course with our planet?

At TEDxMarin, Dr. Ed Lu gave a fascinating talk highlighting the efforts that scientists like himself are making to detect and deflect near-Earth objects.

“You don’t need oil miners and Bruce Willis” to push an asteroid off course, says Dr. Lu. “Deflecting asteroids is not that hard. We have the technology to do something like this.”

Phil Plait: How to defend Earth from asteroids
The bad news? We can’t deflect an asteroid we don’t know is coming. And there are a lot of asteroids out there (check out the jaw-dropping graphics at about 6:00). That’s why Dr. Lu and his team are working on satellites to detect them from space — before it’s too late.